MADISON - Taxpayers are on track to spend $3.5 million to draw and defend election maps approved in 2011 that favor Republicans, state records show.

The cost could be lower than that if Republican lawmakers are successful in their effort to put off an April trial over the maps. Under another scenario, long-running litigation could result in expenses that far surpass $3.5 million.

States have to draw new congressional and legislative districts every 10 years to account for population shifts.

In 2011 Republicans controlled all of Wisconsin's government and put in place maps that have helped them hold large majorities in the Senate and Assembly. GOP lawmakers hired experts and a legal team to make sure the maps were as beneficial to Republicans as possible, court documents and testimony show.

The legal fight over the maps began even before Republicans approved them.

But Senate Republican Leader Scott Fitzgerald of Juneau blamed those who have sued for the costs.

"We didn't pick the fight and all we do is keep trying to defend," he said. "Unfortunately, I think we find ourselves in a position where we're kind of at the whims of all these attorneys that continue to file these lawsuits."

Federal judges in that case upheld the heart of the GOP's redistricting plan but altered the maps for two Assembly districts on Milwaukee's south side that violated the voting rights of Latinos. The judges required the state to cover some of the legal costs of those who brought the lawsuit because they prevailed on their claims that those districts violated voters' rights.

A second lawsuit has been simmering for years and costs for it are set to hit $1.4 million this year.

A panel of federal judges in 2016 ruled 2-1 that the maps were so favorable to Republicans that they violated the voting rights of Democrats. But the U.S. Supreme Court concluded last year those suing over the maps didn't have legal standing to bring the case and sent the lawsuit back to the panel of judges.

Those suing over the maps modified their lawsuit and added more plaintiffs in an attempt to ensure they have legal standing. A trial is slated for April.

Senate and Assembly Republicans in October agreed to pay the Chicago law firm Bartlit Beck up to $840,000 to defend the maps at trial. Those costs come on top of more than $540,000 that has already been paid to other firms.

Assembly Speaker Robin Vos of Rochester for a month refused to release a copy of the contract with Bartlit Beck because he said he believed the contract was a privileged document. He changed course Tuesday and released the contract, though an aide said Vos may withhold legal contracts in the future on the same grounds.